There is known a technique that distributes a packet by broadcasting from a server to a plurality of clients. As the technique that distributes the packet by broadcasting, there is a technique that provides a cache server into a xDSL (xDigital Subscriber Line) accommodation device under an access network, and causes the cache server to copy and distribute the packet (see e.g. Japanese Laid-open Patent Publication No. 2003-69639). According to the technique, useless use of interexchange channels used when the packet distributed from the server is relayed to the clients is omitted.